______________________________________________________________________________ SuSE Security Announcement Package: qpopper Announcement-ID: SuSE-SA:2003:018 Date: Friday, Mar 21th 2003 10:11 MET Affected products: 7.3, 8.0, 8.1 SuSE Linux Enterprise Server 8 Vulnerability Type: remote system compromise Severity (1-10): 3 SuSE default package: no Cross References: CAN-2003-0143 Content of this advisory: 1) security vulnerability resolved: buffer overflow problem description, discussion, solution and upgrade information 2) pending vulnerabilities, solutions, workarounds: - mutt - kernel - ethereal - apcupsd - vnc - openssl - mod_php4 - pgp4pine - nethack - netpbm - man 3) standard appendix (further information) ______________________________________________________________________________ 1) problem description, brief discussion, solution, upgrade information The Post-Office-Protocol- (POP-) Server qpopper (version 4) was vulnerable to a buffer overflow. The buffer overflow occurs after authentication has taken place. Therefore pop-users with a valid account can execute arbitrary code on the system running qpopper. Depending on the setup, the malicious code is run with higher privileges. There is no temporary fix known, please update your system. Please download the update package for your distribution and verify its integrity by the methods listed in section 3) of this announcement. Then, install the package using the command "rpm -Fhv file.rpm" to apply the update. Our maintenance customers are being notified individually. The packages are being offered to install from the maintenance web. Please note, missing packages will be published as soon as possible. Intel i386 Platform: SuSE-8.1: 45017728d71adab5aa1b335878666369 patch rpm(s): 06c56a877950b5285164b77e7818a3df source rpm(s): c8e7be3433bddadc73aac4251faa9b27 SuSE-8.0: e62034de0ab73f1f563950a34047493f patch rpm(s): 0f0b17a2efd99edb840b559095d5b8f0 source rpm(s): 2e8023638bd7c5d71ac5fe55f9bd6036 ______________________________________________________________________________ 2) Pending vulnerabilities in SuSE Distributions and Workarounds: - mutt A buffer overflow in mutt's IMAP code may result in remote system compromise. New packages are currently being build and will be available soon. - kernel A bug in the Linux kernel was found that allows local users to become root. The bug can just be exploited if ptrace(2) is allowed, LKM and kmod support is enabled. We already build new kernels and are currently testing them. As a workaround kernel module loading can be disabled after every boot by executing the following action as root: # echo /just/a/temporary/workaround > /proc/sys/kernel/modprobe Please note, that this will disable some services. - ethereal A format string bug in ethereal's SOCKS handling code and a buffer overflow in the NTLMSSP was found in ethereal. Both bugs may lead to remote system compromise. New packages are currently being build and will be available soon. - apcupsd The control and management daemon for APC UPS systems is vulnerable to remote code execution due to buffer overflow and format string bugs. A dedicated advisory for this issue will be released as soon as all packages are being build. - vnc VNC (Virtual Network Computing) uses a weak cookie generation process which can be exploited by an attacker to bypass authentication. New packages are currently being tested and will be available on our FTP servers soon. - openssl A paper regarding remote timing attacks against OpenSSL has been published by researchers of the Stanford University. It is possible to extract the private RSA key used by services using OpenSSL by observing their timing behavior. Additionally czech researchers found another bug in OpenSSL which is an extension of the "Bleichenbacher Attack". Fixed packages will be available on our FTP servers soon. - mod_php4 4.3.0 A serious security vulnerability was found in mod_php 4.3.0 which allows a remote attacker to read files or even execute PHP-code. This was possible due to direct access to the CGI module. SuSE does not ship this vulnerable version. - pgp4pine A buffer overflow in pine's filter add-on pgp4pine can be abused to execute arbitrary commands remotely. The pgp4pine version SuSE ships is not vulnerable to this bug. - nethack A buffer overflow in nethack can be exploited local users to gain higher privileges if the nethack binary is installed setuid/setgid. This bug is fixed for upcoming SuSE Linux versions. As a temporary workaround you should disable all s-bits on the nethack binary (/etc/permissions.local). - netpbm The netpbm package contains various integer overflows which can lead to arbitrary code execution. New packages are published on our FTP servers. - man A vulnerability in man was published that allows local privilege escalation. SuSE Linux does not ship this vulnerable version of man. ______________________________________________________________________________ 3) standard appendix: authenticity verification, additional information - Package authenticity verification: SuSE update packages are available on many mirror ftp servers all over the world. While this service is being considered valuable and important to the free and open source software community, many users wish to be sure about the origin of the package and its content before installing the package. There are two verification methods that can be used independently from each other to prove the authenticity of a downloaded file or rpm package: 1) md5sums as provided in the (cryptographically signed) announcement. 2) using the internal gpg signatures of the rpm package. 1) execute the command md5sumafter you downloaded the file from a SuSE ftp server or its mirrors. Then, compare the resulting md5sum with the one that is listed in the announcement. Since the announcement containing the checksums is cryptographically signed (usually using the key security@suse.de), the checksums show proof of the authenticity of the package. We disrecommend to subscribe to security lists which cause the email message containing the announcement to be modified so that the signature does not match after transport through the mailing list software. Downsides: You must be able to verify the authenticity of the announcement in the first place. If RPM packages are being rebuilt and a new version of a package is published on the ftp server, all md5 sums for the files are useless. 2) rpm package signatures provide an easy way to verify the authenticity of an rpm package. Use the command rpm -v --checksig to verify the signature of the package, where is the filename of the rpm package that you have downloaded. Of course, package authenticity verification can only target an un-installed rpm package file. Prerequisites: a) gpg is installed b) The package is signed using a certain key. The public part of this key must be installed by the gpg program in the directory ~/.gnupg/ under the user's home directory who performs the signature verification (usually root). You can import the key that is used by SuSE in rpm packages for SuSE Linux by saving this announcement to a file ("announcement.txt") and running the command (do "su -" to be root): gpg --batch; gpg < announcement.txt | gpg --import SuSE Linux distributions version 7.1 and thereafter install the key "build@suse.de" upon installation or upgrade, provided that the package gpg is installed. The file containing the public key is placed at the top-level directory of the first CD (pubring.gpg) and at . - SuSE runs two security mailing lists to which any interested party may subscribe: suse-security@suse.com - general/linux/SuSE security discussion. All SuSE security announcements are sent to this list. To subscribe, send an email to <suse-security-subscribe@suse.com>. suse-security-announce@suse.com - SuSE's announce-only mailing list. Only SuSE's security announcements are sent to this list. To subscribe, send an email to <suse-security-announce-subscribe@suse.com>. For general information or the frequently asked questions (faq) send mail to: <suse-security-info@suse.com> or <suse-security-faq@suse.com> respectively. ==================================================================== SuSE's security contact is <security@suse.com> or <security@suse.de>. The <security@suse.de> public key is listed below. ====================================================================______________________________________________________________________________ The information in this advisory may be distributed or reproduced, provided that the advisory is not modified in any way. In particular, it is desired that the clear-text signature shows proof of the authenticity of the text. SuSE Linux AG makes no warranties of any kind whatsoever with respect to the information contained in this security advisory. Type Bits/KeyID Date User ID pub 2048R/3D25D3D9 1999-03-06 SuSE Security Team <security@suse.de> pub 1024D/9C800ACA 2000-10-19 SuSE Package Signing Key <build@suse.de>